In the deployment of a graft, or stent graft, into the human or animal body via intraluminal techniques, a deployment device is used to introduce the stent graft into a lumen of the body and, after the stent graft has been deployed and expanded within the lumen, the introducer needs to be retracted.
One form of introducer uses a proximal nose cone with a distally facing capsule to encompass an exposed stent and barbs extending from the exposed stent of a stent graft during introduction and, after the stent graft has been released and the capsule has been removed from the exposed stent, the capsule along with the introducer must be withdrawn. The capsule, however, typically has a distally facing opening with an edge surrounding it and this edge can engage with stents of the deployed stent graft and potentially cause problems by dislodging the stent graft from its position on the wall of the lumen.
It is known to provide moveable capsule plugs to facilitate retrieval of introducers. However, known capsule assemblies comprising capsules and capsule plugs, have various shortcomings.
Throughout this specification, the term distal with respect to a portion of the aorta, a deployment device or an endograft means the end of the aorta, deployment device or endograft further away in the direction of blood flow away from the heart and the term proximal means the portion of the aorta, deployment device or end of the endograft nearer to the heart. When applied to other vessels, similar terms such as caudal and cranial should be understood.